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Atrazine, a herbicide widely used in corn production, is frequently detected as pesticide in water resources. In this research, four agricultural fields with a long history of atrazine application in Shiraz and its vicinity in Fars province of Iran, have been studied to determine the fate of atrazine through the passage of time. These four farms were cultivated under a crop rotation (corn-wheat) during the past 10 years. Samples were collected from four soil profiles of 0-10, 10-20, 20-40, and 40-60 cm soil depth at different times. The time intervals for soil sampling started before atrazine application and continued until no atrazine was detected. According to the general linear model, there was no significant difference between atrazine residual concentrations and the soil moisture and depth (p=0.05). But, significant difference between atrazine residual concentrations and the sampling regions was observed (p<0.001). Based on the data, atrazine leaching and dissipation rate in different soil profiles in the four sampling regions were high and significant. Therefore, there is a high risk of atrazine pollution in groundwater resources of the region. [ABSTRACT FROM AUTHOR]

The emergence of drug-resistant strains in tuberculosis treatment underscores the urgency for novel therapeutic approaches. This study investigates the anti-tuberculosis activity of green-synthesized copper oxide (CuO) nanoparticles (NPs) using garlic and astragalus extracts. The physicochemical characterization of the nanoparticles confirms successful synthesis, followed by assessment of their antibacterial properties and safety profile. Rats infected with Mycobacterium tuberculosis are treated with nanocomposites derived from garlic extract at doses of 50 mg/kg and 100 mg/kg body weight. Evaluation includes the analysis of Early secreted antigenic target of 6 kDa (ESAT-6) expression and confirmation of antibodies through molecular assays. Administration of garlic and nanocomposites demonstrates significant inhibitory effects on tuberculosis progression in rats, validated by safety assessments and antibacterial efficacy. Notably, the 100 mg/kg dosage exhibits pronounced mitigation of tuberculosis-induced oxidative stress and lung damage. In conclusion, the combined administration of garlic extracts and green-synthesized nanocomposites shows promising efficacy in reducing tuberculosis infection, highlighting a potential avenue for anti-tuberculosis interventions., Competing Interests: The authors declare that there is no conflict of interest., (© 2024 The Author(s). Food Science & Nutrition published by Wiley Periodicals LLC.)

Background: Nurses are among high-risk occupational groups during the outbreak of epidemics. Therefore, these people are required to use personal protective equipment (PPE). Previous studies have shown that the use of personal protective equipment can affect people's thermal strain and mental workload., Objective: The present study was conducted with the aim of objectively and subjectively evaluating the use of protective clothing on the thermal strain and mental workload of nurses during the covid-19 pandemic., Methods: This cross-sectional study was divided into two groups with a sample size of 300 people who were selected by systematic random method. In the first group, 120 people were objectively evaluated (use of protective clothing). In the second group, 180 people only completed the questionnaire of mental workload, feeling of heat and sweating and other information related to the type of clothing and the duration of its use, etc. Measurements were done in August and September of 2021 and in the morning shift of hospitals. Data were analyzed using SPSS version 21 software and chi-square, independent T-test and linear regression tests., Results: The average age and average working hours per month of the participants in the study were 33.51±7.88 years, 187.91±35.37 hours, respectively. The results showed that the predicted average vote (PMV) index and the predicted percentage of dissatisfied (PPD), moisture felt on the skin surface, the feeling of desirability and pleasantness of the temperature, the weight of sweat and the humidity inside the clothes between the two groups of people using insulated clothes There is a significant difference between medicine and dressing (P < 0.05). There was a significant relationship between mental workload and type of clothing, average working hours per month., Conclusions: The use of medical isolation clothes causes a high heat load on nurses and can increase their mental workload. On the other hand, people using normal gowns suffer from a high mental workload due to the fear of disease due to the uncertainty of high-level protection. In addition, medical isolation clothes increase the humidity of the skin due to their impermeability, which causes skin complications.

Background: Musculoskeletal disorders are one of the most important problems faced by ergonomists today., Objective: This study was conducted with the aim of investigating the effect of weather conditions, working conditions and mental workload on musculoskeletal disorders of rescuers and water and sewage company accidents in hot and cold seasons., Methods: The present study was a longitudinal study that was performed on all employees of rescue and disaster teams of Shiraz Water and Sewerage Company in Iran (184 people) by census. Demographic and Nordic questionnaires, NASA Load Index (NASA-TLX), work environment assessment with temperature screening checklist and workplace ergonomic risk factor (WERA) assessment method were performed by the researcher. The collected data were analyzed using SPSS version 23 software and parametric and non-parametric statistical tests., Results: The results showed that the highest and lowest prevalence of musculoskeletal disorders related to knee and back in winter and thigh in summer with prevalence of 57.1, 55.4 and 6%. The comparison of exposure to heat stress factors in summer and winter seasons showed that the temperature factors and work clothes of the workers in both seasons are in worse conditions than other factors (P < 0968). The results of the mental workload of people in two seasons showed that the highest and lowest mental workload is related to physical changes in the winter season and frustration in the summer season, and this relationship was significant (P < 0.001). Using multiple logistic regression model, the potential risk factors for musculoskeletal injuries including age, height, BMI, level of education and work experience in both hot and cold seasons were compared. The results showed that in summer, work experience (OR = 1.16 (1.06-1.28.)) and height (OR = 1.03(0.98-1.08) had a direct effect on the prevalence of pain and discomfort arranged in the back areas. One year of increase in work experience significantly increases the chance of a disorder in the back by 16% and a one centimeter increase in height increases the chance of a disorder in the lumbar region by 3%, although this relationship is significant., Conclusion: It is recommended that suitable solutions such as using appropriate and up-to-date mechanical tools, reducing activity time, increasing rest time, increasing the number of personnel in order to reduce mental workload, using work clothes suitable for the season and type of work, and ergonomics training for workers are on the agenda of company officials. Water and sewage should be placed.

Objectives. This study aimed to optimize modification of cotton-polyester textiles of workwear in terms of air permeability (AP), bending stiffness (BS) and near-infrared (NIR) reflectance using nanometal-embedded polymethyl methacrylate (PMMA) polymer by a spray method. Methods. This experimental study was carried out to modify cotton-polyester textiles using nanoparticles of aluminum oxide (Al 2 O 3 ), tin oxide (SnO) and zinc oxide (ZnO) embedded in PMMA polymer with different weight percentages by a spray method under 215-psi pressure. The surface temperature of the textiles induced by the NIR spectrum and their comfort in terms of AP and BS were measured according to Standard No. ASTM D737 and BS 3356, respectively. Results. Cotton (65%)-polyester (35%) textiles can be modified with a PMMA-based aluminum and zinc nanoparticle composite with equal weight percentage using a pressurized spray method with good durability. Also, most NIR reflection is in the textile coated with aluminum and ZnO nanoparticle composite in the PMMA base. Conclusions. It is recommended that this composite be used in future studies to impregnate the clothing textile of outdoor workers in hot and arid regions by a spray method under pressure and its effects be investigated on reducing heat stress in these workers.

Objectives. Detection of sensitive signs in many work environments with automated systems (aviation industry, flight safety tower, maritime industry, monitoring in the military industry, etc.) is essential and requires constant visual attention. Therefore, the aim of this study was to investigate the effect of forehead cooling on the accuracy of stable visual attention. Methods. This interventional study was performed on 34 male students. The sampling method was a randomized block design. Subjects were assessed by demographic questionnaire, Snellen chart, Spielberger state-trait anxiety inventory (STAI) and physiological and cognitive measurements. Results . Prefrontal cortex (PFC) cooling caused significant changes in sublingual temperature during four measurements in the intervention group. There were no significant changes in heart rate, diastolic blood pressure and saturation of peripheral oxygen (%SpO 2 ) between the two groups. The critical flicker frequency (CFF) as an indicator of cognitive fatigue showed that cognitive improvement after PFC cooling occurred following a reduction in cognitive fatigue. Conclusions. Considering the importance of choosing non-invasive methods to improve the operator's cognitive skills while performing cognitive tasks in the field of neuroergonomics, it can be concluded that PFC cooling is an effective and safe way to improve some cognitive skills such as visual attention.

Background: Non-technical skills are cognitive and social skills that are necessary for safe and efficient practices in operating theatre. These skills are inseparable parts of circulating nurses' duties and help them have a good performance during surgical processes. Circulating nurses' non-technical skills have not been closely measured, and much uncertainty still exists about the quality of their skills. This study aimed to assess circulating nurses' non-technical skills., Methods: A cross-sectional study was conducted on 300 circulating nurses who worked in four public hospitals in Iran, during 2020. The data of demographics of the studied population were collected using a demographic questionnaire. Kalantari et al's Circulating Practitioner's List of Non-Technical Skills was used to assess the circulating nurses' non-technical skills., Results: The situational awareness domain had the highest score, while leadership was the domain with the lowest mean score. There was a moderate positive relationship between the mean score of non-technical skills and the number of working years as a circulating nurse., Conclusion: Although the circulating nurses had a moderate level of non-technical skills, they had low scores in several behaviours. However, they did well in some other behaviours. Educational interventions and policymaking solutions can help improve circulating nurses' non-technical skills., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

The present study investigated the short-term effects of using Personal Protective Equipment (PPE) and physical workload intensity on human physiological and cognitive performance among 21 males and 19 females. PPE1 consisted of a medical coverall and surgical mask, while PPE2 consisted of impermeable full-body coverall, shoe covers, latex gloves, N95 mask, and face shield. Objective assessments were heart rate, energy expenditure, core body temperature, clothing microclimate temperature and humidity, and cognitive performance were the continuous performance test and N-Back test. Subjective assessments included thermal sensation, perceived fatigue/skin wetness/clothing moisture. Using PPE2 and increased workload intensity significantly increased the values of all physiological parameters and the subjective ratings of fatigue, thermal sensation, skin wetness, and clothing moisture. Moreover, the participants' cognitive performance was not affected by the type of PPE. Practitioner summary: Healthcare workers are at the highest risk in the fight against pandemics. Therefore, these people are required to use personal protective equipment. Using this equipment may have difficulties. The results show physiological strain and higher subjective ratings associated with using full-body hospital PPE and increased physical workload.

The cement industry is one of the main world industries with exposure to a wide range of hazardous chemical and physical occupational agents that may increase free radicals and lead to disease. The aim of this study was to evaluate oxidative stress, biochemical markers, and psychological parameters among cement plant workers. In this cross-sectional study, 40 workers exposed to cement and 40 office employees were selected as the exposed and non-exposed groups, respectively. Exposure to cement dust, silica, and noise were, respectively, assessed using the NIOSH 0600, NIOSH 7601, and noise dosimetry methods. Oxidative stress biomarkers including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC), and biochemical parameters were measured in the serum of all participants. Depression, anxiety, and stress were assessed by the Depression Anxiety Stress Scales (DASS-21) questionnaire. The results demonstrated that the level of MDA as a marker of oxidative stress was significantly higher in the exposed group. The level of antioxidant enzymes including SOD and CAT were also significantly higher in the exposed group. The level of TAC was lower in the exposed group, but the difference was not statistically significant. The levels of alkaline phosphatase (ALP), aspartate transaminase (AST), and the scores of depression and stress were also significantly higher in the exposed group. According to our results, noise, cement dust, and silica exposure were associated with oxidative stress, and this may be one of the mechanisms in which they adversely affect liver function and mental health.

Background: The intensive care unit (ICU) is a complex, dynamic, high stress and time-sensitive place. While a variety of rules and regulations provided to reduce medication errors in recent years, many studies have emphasized that medication errors still happen., Objective: The purpose of this investigation is to predict, reveal and assess medication errors among surgical intensive care unit (SICU) nurses., Methods: This study was performed in one of the public hospitals in Shiraz, namely Shahid Faghihi hospital. The human error assessment and reduction technique (HEART) method was adopted to measure and assess medication errors in the ICU., Results: Findings indicate that ICU nurses perform 27 main tasks and 125 sub-tasks. The results also showed that setting and using DC shock task has the highest human error probability value, and assessment of patients by a nutritionist has the lowest human error probability value., Conclusion: Medical errors are key challenges in the ICU. Therefore, alternative solutions to mitigate medication errors and enhance patient safety in the ICU are necessary. Although the technique can be used in healthcare; there is a need to localize the coefficients and definitions to achieve more accurate results and take appropriate controls. Employing experienced people and providing conditions that reduce the possibility of errors in nurses, increasing the number of staff, and developing specialized and simulated training were identified as the most important control strategies to reduce errors in nurses.

Background: Nontechnical skills are necessary for clinicians' safe performance and prevention of errors in the operating room. Educational intervention is a useful way to improve these skills, which are a vital area for improvement. Circulating nurses are surgical team members whose work depends heavily on using nontechnical skills. This study is aimed at assessing the effect of an educational intervention on the improvement of circulating nurses' nontechnical skills., Methods: This semiexperimental study was conducted on 300 circulating nurses divided into the intervention and no intervention groups each containing 150 participants. The nontechnical skills were assessed using the circulating practitioners' list of nontechnical skills. Then, the intervention group received training regarding these skills, and the two groups were evaluated again. After all, the data were entered into the SPSS 24 software and were analyzed using descriptive statistics and Wilcoxon and Mann-Whitney tests. Furthermore, Kendall's tau, independent sample t -test, and one-way ANOVA were used for assessment of relationship between median scores and demographics., Results: The results revealed a significant improvement in the scores of all domains of nontechnical skills in the intervention group ( p < 0.05). The highest and lowest improvements were observed in teamwork (42%) and situational awareness (16.7%), respectively. After the intervention, the scores of some of the behaviors were still below the average level or were not improved significantly., Conclusions: Circulating nurses' nontechnical skills can be improved by educational interventions. However, regarding the low scores or no improvements in the scores of some behaviors, other intervention types such as policymaking and correcting the existing hierarchies in the operating room can be useful to complete the educational interventions., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Reza Kalantari et al.)

Introduction: The mental health of people working in Covid-19 wards (nurses, doctors, etc.) may be compromised due to the specific conditions of the workplace and patients. Therefore, the aim of this study was to investigate the relationship between mental burden and quality of work life in nurses in intensive care units of Covid-19 patients., Method: In this cross-sectional study, a sample of 200 people-100 nurses in care units for patients with COVID-19 (group 1) and 100 nurses in non-COVID-19 patient care units (group 2-in three university hospitals were obtained. These 200 samples were randomly extracted from the list of employees and selected. Data were collected using three questionnaires, including (1) a demographic, (2) the NASA-Task Load Index (1988) (Hart & Staveland, 1988) and (3) National Institute for Occupational Safety and Health (NIOSH) Quality of Life. Data were analyzed using SPSS-24 software and descriptive and analytical statistical methods., Results: The overall mean scores of nurses' quality of work life were significantly different between the two groups (P < 0.05). The average score of quality of life in nurses caring for patients with COVID-19 is 92.57, more than nurses caring for patients without COVID-19, 79.43. Among the dimensions of mental workload: Performance and efficiency, with an average score of 77.32 ± 15.85, had the highest score, while discouragement and failure, with an average score of 58.04 ± 26.72, had the lowest score of mental workload. There is a significant difference between the mental load of work in the two groups (P = 0.001). There is a significant inverse relationship between total quality of work life and total mental workload (r = -14 and P = 0.01)., Conclusion: In this study, it was observed that nurses caring for Covid-19 patients are in a more unfavorable situation in terms of the studied characteristics. Due to the work period, these nurses have a high workload and a low quality of work life to compensate for the mental and physical deficiencies required by a long presence in the work environment., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2021 The Author(s).)

Objective: To review beneficial effects of red clover (Trifolium pratense L.) on biological processes., Methods: A systematic review was carried out according tothe PRISMA checklist. Using MeSH keywords, 385 articles were extracted from national and international databases (PubMed, Science Direct, SID, and Google Scholar search engine) without time limit. After removing duplicates, 80 articles were reviewed., Results: Our findings revealed that the compositions of red clover promote anti-oxidant and anti-cancer effects. Furthermore, they exude beneficial effects on cardiovascular functionand improvesymptoms of menopause. Also, these compounds can regulate blood glucose and lipid markers. The effects of the herb on have also been investigated on various tissues including endometrium, breast, skin and reproductive system., Conclusion: In recent studies, the anti-cancer effects of clover (Trifolium) extract co-administrated with standard drugs have been reportedin different cancers.

Background: Manual assembly workers are exposed to risk factors of musculoskeletal disorders. The most important risk factor among the workers is static and awkward posture. This study aimed to the ergonomic design of manual assembly workstation using Digital Human Modeling (DHM)., Methods: This cross-sectional study was conducted among manual assembly workers. Data was gathered via 1) demographic/occupational questionnaire, 2) The Persian version of the Nordic General Questionnaire (P-NMQ), 3) Rapid Upper Limb Assessment (RULA) using Kinect sensor, 4) Hierarchical Task Analysis (HTA), 5) Idea Rating Sheet (IRS), 6) Anthropometric data of the participants, 7) CATIA software and RULA technique., Results: The results of the evaluations showed that in the design of most workstations of assemblers in Shiraz electronics industries, complete ergonomic principles were not observed, and the implementation of targeted ergonomic interventions in them is necessary., Conclusion: The prevalence of musculoskeletal symptoms is high among manual assembly workers. The RULA technique showed that the designed manual assembly workstation using DHM effectively could improve the subjects' awkward postures., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2021 The Author(s).)

Background: Understanding the causes and risk factors of metabolic syndrome is important for promoting population health. Oxidative stress has been associated with metabolic syndrome, and also obstructive sleep apnea. These are two diseases which have common prognostic characteristics for heart disease. The aim of this study was to examine the role of oxidative stress in the concurrent presence of metabolic syndrome and obstructive sleep apnea in a working population., Methods: Participants were 163 artisan bakers in Shahroud, Iran, routinely exposed to significant heat stress and other oxidative stress indicators on a daily basis as part of their work. Using a cross-sectional design, data relevant to determining metabolic syndrome status according to International Diabetes Federation criteria, and the presence of obstructive sleep apnea according to the STOP-Bang score, was collected. Analyses included hierarchical binary logistic regression to yield predictors of the two diseases., Results: Hierarchical binary logistic regression showed that oxidative stress - alongside obesity, no regular exercise, and smoking - was an independent predictor of metabolic syndrome, but not obstructive sleep apnea. Participants who were obese were 28 times more likely to have metabolic syndrome (OR 28.59, 95% CI 4.91-63.02) and 44 times more likely to have obstructive sleep apnea (OR 44.48, 95% CI 4.91-403.28). Participants meeting metabolic syndrome criteria had significantly higher levels of malondialdehyde (p <  0.05) than those who did not. No difference in oxidative stress index levels were found according to obstructive sleep apnea status., Conclusions: Our findings suggest that oxidative stress contributes to the onset of metabolic syndrome, and that obstructive sleep apnea is involved in oxidative stress. Whilst obesity, exercise, and smoking remain important targets for reducing the incidence of metabolic syndrome and obstructive sleep apnea, policies to control risks of prolonged exposure to oxidative stress are also relevant in occupations where such environmental conditions exist.

Researchers have always been interested in finding new and effective materials for protection against radiation. This experimental study aimed to design and fabricate new types of nano-material and micro-material based shields against the ionizing effect of cone beam computed tomography (CBCT) X-rays. To fabricate a flexible prototype, we added dioctyl phthalate (DOP) oil to emulsion polyvinyl chloride (PVC) powder. The paste was mixed and dispersed. Then, nano- and micro-powders of WO 3 and Bi 2 O 3 were added to the paste, with the weight ratio of 20% PVC, 20% DOP, and 60% nano- and micro-metals. Using an ultrasonic mixer, the polymer matrix and metals were mixed and a paste with a thick texture was developed. The resultant paste was poured into glass molds and the molds were then heated in an oven. After cooling, the resultant sheets were selected for further experiments. A CBCT unit and dosimeter were used to evaluate the characterization and X-ray shielding properties of the fabricated prototypes. The half-value layers (HVL) for nano-WO 3 , micro-WO 3 , nano-Bi 2 O 3 , and micro-Bi 2 O 3 were 0.0390, 0.0524, 0.0351, and 0.0374 cm, respectively. In addition, the linear attenuation coefficient (µ) for these materials were 17.77, 13.20, 19.71, and 18.5 cm -1 , respectively. The findings indicate that nano-structured samples are more effective in the attenuation of X-ray energy. The nano-structured WO 3 prototype was nearly 34% more efficient in attenuating radiation compared to the micro-structured WO 3 prototype. This difference in nano- and micro-structured Bi 2 O 3 prototypes was 6.5%., Competing Interests: The authors declare no conflict of interest

Competing Interests: Conflict of interest The authors declare that there is no conflict of interests.

Coronavirus disease of 2019 (COVID-19) started in December 2019 in Wuhan, China. In a few months, it has become a pandemic with devastating consequences for the global economy. By the end of June, with almost 2.6 million confirmed COVID-19 cases, United States is above other countries in the rankings. Furthermore, New York with more than 416 thousand cases is the epicenter of outbreak in the US and had more cases than any other countries in the world until first half of June. In this paper, we use a two-step Vector Auto Regressive (VAR) model to forecast the effect of the virus outbreak on the economic output of the New York state. In our model, we forecast the effect of the shutdown on New York's Gross Domestic Product (GDP) working with Unemployment Insurance Claim series representing a workforce factor, as well as the Metropolitan Transportation Authority (MTA) ridership data indicating the economic activity. We predict annualized quarterly growth rate of real GDP to be between -3.99 to -4.299% for the first quarter and between -19.79 to -21.67% for the second quarter of 2020., (© Springer Nature Switzerland AG 2020.)

Background: Breastfeeding is considered as a protective factor against non-communicable diseases in infants and mothers. The first aim of this study was to assess the influence of ergonomic breastfeeding training on the infants' growth. The second aim was to investigate the effectiveness of this training for improving musculoskeletal disorders in mothers., Methods: In this randomized control trial, 104 participants who were referred to the health centers in Shiraz for breastfeeding care were randomly allocated into the intervention or comparison group using a size-four block sampling method. At birth, 2, 4, and 6 months later childbirth, Rapid Upper Limb Assessment was used to assess musculoskeletal disorders in participants , and the severity of their discomfort was measured with the Visual Analog Scale. During the 6 months of the study (March to September, 2017), the weight and height of the neonates were measured every 2 months., Results: Significant differences were found between groups in the priority level for corrective action in mothers' postures determined by Rapid Upper Limb Assessment at 2, 4 and 6 months after childbirth ( p  < 0.001). Based on the Visual Analog Scale results in mothers at 6 months after childbirth, fewer back pain was reported by the intervention group ( p  = 0.03). No significant difference were found in the infants ' weights and heights in boys and girls at all growing stages between the two study groups ( p  > 0.05). However, the mean height for age of the girl infants at age of 6 months was higher among intervention groups compared to the controls ( p  = 0.01)., Conclusion: This study demonstrated that ergonomic breastfeeding training reduced the incidence of musculoskeletal disorders in mothers but seems not to have any significant and consistent impact on the infants' growth., Trial Registration: fa.irct.ir IRCT2014042317398N1., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2019.)

Background: Whole-body vibration (WBV) and mental workload (MWL) are common stressors among drivers who attempt to control numerous variables while driving a car, bus, or train., Objective: To examine the individual and combined effects of the WBV and MWL on the autonomic nervous system., Methods: ECG of 24 healthy male students was recorded using NeXus-4 while performing two difficulty levels of a computerized dual task and when they were exposing to WBV (intensity 0.5 m/s 2 ; frequency 3-20 Hz). Each condition was examined for 5 min individually and combined. Inter-beat intervals were extracted from ECG records. The time-domain and frequency-domain heart rate variability parameters were then extracted from the inter-beat intervals data., Results: A significant (p=0.008) increase was observed in the mean RR interval while the participants were exposed to WBV; there was a significant (p=0.02) reduction in the mean RR interval while the participants were performing the MWL. WBV (p=0.02) and MWL significantly (p<0.001) increased the standard deviation of normal-to-normal intervals with a moderate-to-large effect size. All active periods increased the low-frequency component and low-frequency/high-frequency ratio. However, only the WBV significantly increased the highfrequency component. A significant (p=0.01) interaction was observed between the WBV and MWL on low-frequency component and low-frequency/high-frequency ratio., Conclusion: Exposure to WBV and MWL can dysregulate the autonomic nervous system. WBV stimulates both sympathetic and parasympathetic nervous system; MWL largely affects sympathetic nervous system. Both variables imbalance the sympatho-vagal control as well.

Background: Previous studies have reported impaired performance, sleepiness and sleep deprivation among night workers. The purpose of this study was to investigate the effect of color screen Light Filtering software on cognitive performance, alertness and sleep quality among night shift operators of a medical emergency operations center. Methods: This field trial interventional study was carried out among 30 nightshift operators of shiraz emergency control center. The baseline assessments were carried out under the existing computer screen light conditions in the week preceding the installation of f.lux software. The same measurements were repeated again 4 weeks after installing the software. The cognitive performance of the participants was measured using continuous performance test (CPT) and n-back, while their sleep quality was assessed through Pietersburg Sleep Quality Index (PSQI). Further, to assess their subjective and objective alertness, Stanford sleepiness index and go/nogo test were used, respectively. Results: The results of this study showed that Screen Light Filtering software significantly increased subjective (P<0.001) and objective alertness (P<0.05). Additionally, the performance of the working memory (P=0.008) and sleep quality (P=0.008) improved significantly after the intervention. Conclusion: The results revealed that using Screen Light Filtering software is an effective and low-cost method to improve sleep quality and cognitive performance since it filters the short wavelength part of the spectrum and helps body adaptation.

Introduction: Assessing the work ability and factors affecting it is essential in developing strategies for preventing damages and managing risks. This study aimed to investigate the simultaneous effect of noise level and physiological strain as well as individual characteristics on the work ability., Method: The population in this cross-sectional study included workers of a rubber factory. The TES noise dosimeter was used to examine individual exposure and the electro polar RS100 was used to measure physiological strain index (PSI). Individual characteristics and the work ability index were evaluated using the WAI questionnaire and analyzed using SPSS version 19. chi-square test, pearson correlation coefficient, and one-way and multiple ANOVA were used for data analysis., Results: The final modeling showed that age, exercising period, Equivalent Continuous Sound Pressure Level (Leq), PSI and employment status had significant correlations with the work ability index (p &lt; 0.05). The modified r2 for the obtained model was also calculated to be 0.483., Discussion and Conclusion: Based on the findings, number of exercising hours, employment status, age, Leq, and psi are among the factors affecting the work ability index. Use of management and engineering controls are recommended to balance work environments exposed to noise and heat and improve the work ability index. Further, improving employment status due to creating a sense of stability and reducing stress as well as enhancing lifestyle quality can be effective in increasing the work ability index., Competing Interests: The authors have no competing interests to declare., (© 2019 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/.)

Background: Welding is a common industrial process and is harmful to welders' health., Objective: To determine the effect of toxic gases and metal fumes produced during 3 welding processes on welders' incidence of respiratory symptoms and pulmonary function., Methods: This cross-sectional study was conducted in an Iranian shipbuilding industrial factory in 2018. Using the simple census method, 60 welders were selected as the exposed group. 45 staff members of the administrative unit were also recruited to be served as the control group. Welders' demographic data and respiratory complaints were collected employing a questionnaire. Fumes and gases produced were sampled from the welders' respiratory tract and analyzed by standard methods suggested by the National Institute of Occupational Safety and Health (NIOSH). Pulmonary function test was also performed for each participant., Results: The prevalence of respiratory symptoms in all welders was significantly (p<0.05) higher than the control group. The mean FVC, FEV 1 and FEV 1 /FVC measured in welders involved in all 3 processes were significantly lower than those recorded in the control group. The spirometry pattern in welders involved in flux cored arc welding and shielded metal arc welding was obstructive; that in those involved in gas metal arch welding was mixed (obstructive and restrictive pattern)., Conclusion: Exposure to welding fumes and gases was associated with pulmonary function deterioration. Welders involved in gas metal arch welding had a higher prevalence of pulmonary disorders compared with those involved in gas metal arch welding and flux cored arc welding.

Background: Petrol is an integral ingredient in industrial world. According to the US Agency for Toxic Substances and Disease Registry, there are typically more than 150 chemicals in petrol, including small amounts of benzene, toluene, xylene, ethyl benzene, and trace amounts of some contaminants, such as lead. The aim of this study was to measure the possible deleterious effect of long-term exposure to petrol on blood parameters and liver function., Methods: This is a case-control study conducted on 160 participants. Among them, 80 participants worked in a gas station for at least 4 years and 80 participants appeared with no history of occupational exposure to petrol. Blood sample was taken at the time of admonition to the tardive office at each station at 10 AM to measure the association of number of total and differential leukocyte and liver functions., Results: Based on the results, significant reduction in total leukocyte numbers was found in exposed group compared to unexposed group (1347 ± 4.59, <0.001). However, there was a significant increase in neutrophil (75.9 ± 3.50 in exposed group compared with 58.9 ± 3.15 among unexposed group, P < 0.001). However, no significant difference was found in liver enzymes between both groups., Conclusions: Long-term exposure to petrol fumes has deleterious effect on white blood cells. A significant reduction in the number of total and differential lymphocyte seems to be attributed to the toxic effect of petrol ingredients., Competing Interests: There are no conflicts of interest.

The current study evaluated the inhalation toxicity of trichloroethylene (TCE) at 0, 10, 100, 250 and 400 ppm in Sprague-Dawley rats for 10 day period, because the subacute inhalation toxicity of TCE on serum lipid profile, glucose and some biochemical parameters has not been previously reported. TCE vapors were generated using the dynamic generation system based on evaporation method in the exposure chamber. On the basis of the results, mean serum low-density lipoprotein (LDL) and albumin (ALB) decreased significantly in all the groups exposed to TCE compared with the control group (p < .005), but there was a significant increase for parameters: fasting blood glucose (FBG) and alkaline phosphatase (ALP) (p < .005). Rats exposed to 400 ppm TCE showed a significant decrease in serum cholesterol (CHOL) and protein (Pr) compared with the control group (p < .005). A negative relationship was found between triglycerides (TG), very low density lipoprotein (VLDL), CHOL, LDL, Pr, ALB and urea levels and the subacute exposure to concentrations of TCE (R 2  = -0.26, p < .05), but there was a direct correlation for parameters FBG, ALP and alanine aminotransferase (ALT) (R 2  = 0.42, p < .05). In conclusion, studies with Sprague-Dawley rats demonstrated that subacute inhalation exposure to TCE (≥ 100 PPM) is associated with biochemical and lipotoxicity in the form of decreased serum ALB and LDL and raised ALP and glucose levels. The present study also provides additional evidence relating to decreased serum CHOL and Pr after subacute inhalation exposure to 400 ppm TCE.

Background: Thermal component of the atmospheric environment is an important issue which is related to human's health. Thermal environment includes both heat exchange conditions (stress) and the physiological response (strain). The aim of this study was to measure the association of heat indices (PSI, HSI, Humidex) especially subjective one (STI) with some physiological parameters (Blood pressure, pulse rate and skin temperature)., Methods: This is a cross-sectional study conducted on 387 male farmers on Boukan, West Azerbaijan, Iran in 2016. Sampling was conducted on the hottest days in summer on July based on the meteorological report. Heat parameters was measured 3 times in each session ., Results: Direct associations were found between heat indices and physiological parameters except systolic BP. However, invers associations were found between blood pressure, skin and core body temperature, pulse rate with all heat indices. Based on the results of linear regression analysis, significant association was found between WBGT and skin temperature (B = 0.31, CI: 0.02, 0.61, P  = 0.03). Results also showed significant association between Humidex and skin temperature (B = 0.21, CI: -0.03, 0.40, P  = 0.02). However, no significant associations were found between other heat stress indices including UTCI, PHS, HIS, STI and Humidex with all study physiological parameters (core body temperature, systolic and diastolic blood pressure and also pulse rate)., Conclusion: As expected, farmer's health is affected by physiological parameters. Moreover, among assessed types of heat stress indices WBGT and Humidex were more powerful to show better the association with mentioned physiological parameters .

Background: Firefighters for difficult activities and rescue of damaged people must be in appropriate physical ability. Maximal oxygen capacity is an indicator for diagnosis of physical ability of workers. This study aimed to assess the cardiorespiratory system and its related factors in firefighters., Methods: This study was conducted on 110 firefighters from various stations. An self-administered questionnaire (respiratory disorders questionnaire, Tuxworth-Shahnavaz step test, and pulmonary function test) was used to collection of required data. Average of humidity and temperature was 52% and 17°C, respectively. Background average noise levels were between 55 and 65 dB. Data were analyzed using SPSS software (version 19)., Results: The mean age of the study participants was 32 ± 6.2 years. The means of forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and FEV1/FVC were 92% ±9.4%, 87% ±9.2%, and 80% ±6.1%, respectively. The participants' mean VO 2 -max was 2.79 ± 0.29 L/min or 37.34 ± 4.27 ml/kg body weight per minute. The results revealed that weight has a direct association with vital capacity (VC), FVC, and peak expiratory flow. In addition, height was directly associated with VC, FVC, and VO 2 -max ( P < 0.05). However, there was an inverse and significant association between height and FEV1/FVC ( r = -0.23, P < 0.05). Height, weight, body mass index, and waist circumference were directly associated with VO 2 -max., Conclusions: The findings of this study showed that the amount of maximum oxygen consumption is close with the proposed range of this parameter among firefighters in other studies. Furthermore, the results of the study revealed that individuals had normal amounts of lung volume index. This issue can be attributed to the appropriate usage of respiratory masks., Competing Interests: There are no conflicts of interest.

Objectives: Work ability is a crucial occupational health issue in health care settings where a high physical and psychosocial work capacity is required and a high risk of disabling injuries and illnesses is predictable. This study aims to examine the association between the work ability index (WAI) and individual characterizations, workload, fatigue, and diseases among intensive care units' (ICUs') nurses., Methods: The study sample included 214 nurses selected by a random sampling method from a target population consisting of 321 registered nurses working in eight ICUs. Multiple linear regression analysis was used to test the association between WAI scores and each of the independent variables., Results: Results of multivariate analysis revealed a strong and negative association between WAI scores and diseases (B=-5.82, 95% CI=-7.16, -4.48, P<0.001). Among the studied individual characterizations, body mass index (BMI) was significantly and inversely associated with WAI scores. A significant and negative association was also found between WAI scores and dimensions of MFI-20, such as general fatigue (B=-0.31, 95% CI=-0.53, -0.09, P=0.005) and physical fatigue (B=-0.44, 95% CI=-0.65, -0.23, P<0.001). From dimensions of workload, frustration (B=-0.04, 95% CI=-0.07, -0.02, P<0.001) and temporary demand (B=-0.04, 95% CI=-0.08, -0.0001, P=0.04) showed a negative and significant association with WAI scores, while performance showed a positive and significant association (B=0.04, 95% CI=0.01, 0.07, P=0.005)., Conclusions: Based on the study findings, development of health care programs with the aim of setting up a healthy work environment characterized by a well-structured preventive attitude toward controlling diseases, and a well-designed organizational framework toward increasing the level of performance and motivation, reducing the level of fatigue, as well as reducing the workload, is necessary to promote work ability among ICUs' nurses.

Introduction: Sound is among the significant environmental factors for people's health, and it has an important role in both physical and psychological injuries, and it also affects individuals' performance and productivity. The aim of this study was to determine the effect of exposure to high noise levels on the performance and rate of error in manual activities., Methods: This was an interventional study conducted on 50 students at Shiraz University of Medical Sciences (25 males and 25 females) in which each person was considered as its own control to assess the effect of noise on her or his performance at the sound levels of 70, 90, and 110 dB by using two factors of physical features and the creation of different conditions of sound source as well as applying the Two-Arm coordination Test. The data were analyzed using SPSS version 16. Repeated measurements were used to compare the length of performance as well as the errors measured in the test., Results: Based on the results, we found a direct and significant association between the levels of sound and the length of performance. Moreover, the participant's performance was significantly different for different sound levels (at 110 dB as opposed to 70 and 90 dB, p < 0.05 and p < 0.001, respectively)., Conclusion: This study found that a sound level of 110 dB had an important effect on the individuals' performances, i.e., the performances were decreased.

Introduction: Sleep disorders are the cause of morbidity and mortality and can decrease functional capacity and quality of life. Nurses, especially those working irregular or night shifts, are at risk for developing sleep disorders. The present study aims to determine the relationship between sleep quality and health-related quality of life (HRQOL) as well as quantitative and subjective aspects of sleep quality in nurses., Methods: This cross-sectional study was conducted on 1456 nurses working in 11 hospitals in Shiraz and Tehran (Iran) in 2014. Structured questionnaires (Pittsburg Sleep Quality Index [PSQI] and Medical Outcomes Study Short Form-36 Survey [SF-36]) were used to collect data on participants' demographic characteristics, sleep quality, and health-related quality of life. Chi-square and independent samples t-test were employed for statistical analysis., Results: Mean age of participants was 30.81 ± 7.8, and most of them were female (89.04%) and poor sleepers. Long-duration sleepers slept for more than 9.8 h/night, and they obtained higher scores than short-duration sleepers (<4.5 h/night) in all SF-36 domains. The study results showed that increased quality of life was significantly related to health-related quality of life., Conclusions: This study showed strong evidence that sleep disorders, such as poor quality and short duration of sleep, are negatively associated with HRQOL. Therefore, developing systemic strategies to cope with the problem seems to be necessary.

Purpose: Gioblastoma multiforme as a chemoresistant and radioresistant malignant cell line needs to novel strategies to treatment. Low-dose hyper-radiosensitivity (LDHRS) seems to be an effective phenomenon to irradiation that can save normal brain fibroblasts. Genistein which is a soy isoflavone can be cytotoxic in some tumor cell lines. So we determined to study the effect of combining these two treatment modalities., Materials and Methods: After 30 hours incubation with Genistein in different concentrations on U87MG cell line, proliferation and clonogenicity were conducted by both clonogenic and MTT assays. A conventional 2Gy radiation dose was compared with 10 doses of 0.2Gy gamma irradiation with 3 minutes and 1 hour intervals. Finally, concurrent effect of these modalities was assessed., Results: Based on acquired cell doubling time (30 hours), one doubling time treatment by Genistein could decrease clonogenicity. U87MG cell line exhibited HRS at low dose irradiations. 2Gy irradiation was more effective than ultra-fractionation methods in comparison with control group. All groups with 50uM concentration of Genistein showed decrease in the survival. This decrease compared with control group, in 10x0.2Gy with 3 minutes intervals plus 50uM Genistein was significant and for groups with the same dose of Genistein but along with continuous 2Gy was more significant., Conclusion: In one day treatment regimen, 10x0.2Gy ultra-fractionation with 3 minutes and 1 hour intervals seems to be less effective than conventional 2Gy irradiation, however adding 50uM Genistein can decrease survival more. Although 2Gy conventional dose plus 50uM Genistein was the most effective regimen., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Welding is among the most important frequently used processes in the industry with a wide range of applications from the food industry to aerospace and from precision tools to shipbuilding. The aim of this study was to assess the level of steel industry welders' exposure to ultraviolet (UV) radiation and to investigate the health impacts of these exposures., Methods: In this case-control study, we measured the intensity of UV at the workers' wrist in Fars Steel Company through manufacture of different types of heavy metal structures, using UV-meter model 666230 made by Leybold Co., from Germany., Results: The population under the study comprised 400 people including 200 welders as the exposed group and 200 nonwelders as the unexposed group. The results of the questionnaire were analyzed using SPSS software, version 19. The average, standard deviation, maximum and minimum of the UV at the welders' wrist were 0.362, 0.346, 1.27, and 0.01 μW/cm(2), respectively. There was a significantly (P < 0.01) higher incidence of cataracts, keratoconjunctivitis, dermatitis and erythema in welders than in their nonwelders., Conclusions: This study showed that the time period of UV exposure in welders is higher than the permissible contact threshold level. Therefore, considering the outbreak of the eye and skin disorders in the welders, decreasing exposure time, reducing UV radiation level, and using personal protective equipment seem indispensable. As exposure to UV radiation can be linked to different types of skin cancer, skin aging, and cataract, welders should be advised to decrease their occupational exposures.

Background: This study assessed the effect of supplementation of omega-3 fatty acids and ascorbic acid alone and in combination on the level of lipid peroxidation (malondialdehyde, MDA concentration), total antioxidant capacity (TAC) and depression scores in depressed rotational shift workers in the Tehran Shahid Tondgoyan Oil refinery., Material and Methods: In this randomized, double-blind, placebo-controlled trial, 136 men who met the inclusion and exclusion criteria and had a Beck Depression Inventory (BDI) score ≥ 10 were selected. Among the participants, 33 received omega-3 fatty acid soft gel (1000 mg twice daily) with vitamin C (250 mg twice daily) (group 1), 31 took omega-3 fatty acid supplements and vitamin C placebo (group 2), 30 took omega-3 fatty acid supplement placebo and vitamin C (group 3), and 32 received omega-3 fatty acid supplement placebo and vitamin C placebo (group 4) for 2 months. Measured were serum MDA, TAC concentrations, and BDI scores at baseline and after 2 months., Results: This study showed that the BDI score was reduced significantly in all 4 groups, however, the level of decrease was more in the omega-3 fatty acid (alone) supplementation group (mean 6.29 score decrease) (p < 0.001). MDA level decreased significantly in groups with omega-3 fatty acids (mean 0.78 μmol/L ± 1.64 μmol/L decrease) (p = 0.014) or vitamin C supplementation alone (mean 0.74 μmol/L ± 1.55 μmol/L decrease) (p = 0.014), but not in combination., Conclusions: Supplementation of omega-3 fatty acids alone and not in combination with vitamin C had a better impact on depression and MDA level pronounced in depressed male shift workers.

Background: About 20 to 50 percent of accidents are due to some forms of carelessness and mindedness. Studies suggested that vibration is one of the most important physical factors in human performance when traveling on any sort of vehicles. The aim of this study was to investigate the effect of vehicles vibration on cognitive performance (attention and concentration)., Methods: The sample consists of 25 male students who undergone 4 experimental phases: acceleration low vibration (0.53 m/s(2)), medium vibration (0.81 m/s(2)), high vibration (1.12 m/s(2)) and non- exposure to vibration (control phase) according to ISO 2631-1 standard and with fixed frequency between 3 to 7 Hz. Students paired T test was applied to analysis the data, using SPSS software ver. 19., Results: The mean number of correct answers obtained from selective attention test under vibration levels of 0.53 m/s(2) and 0.81 m/s(2) were significantly lower than the condition without vibration. The mean reaction time of divided attention test in three vibration levels was significantly lower than the condition without vibration. Exposing to vibration reduces number of correct answers, selective attention and reaction time., Conclusion: In this study, it was found that vibration may disrupt the ability of the participants for sustainability attention. It also changes the precision and speed of humans' information processing systems.

Objective: The aim of this study was to determine the oxidative stress; serum level of Total Antioxidant Capacity (TAC)and Malondialdehyde (MDA) level and the depression score among the depressed rotational shift workers in Shahid Tondgouyan Refinery in Tehran (Iran)., Methods: A cross-sectional study was conducted among all the 189 shift workers in Shahid Tondgouyan oil refinery who were eligible to participate in the study. They did not take any antidepressants for two months or any supplements for two weeks prior to the study entry. Written consent was obtained from the participants. 21- Item Beck Depression Inventory was used to measure the depression level. Furthermore, body weight, height and systolic and diastolic blood pressure were collected from all the participants. The levels of Total Antioxidant Capacity (TAC) and Malondialdehyde (MDA) were measured by 8 ml fasting blood sample. MDA was determined by thiobarbituric acid reaction. Serum total antioxidants were measured using the spectrophotometric ABTS. In the ABTS test, 2,2'-azinobis (3-ethylbenzthiazoline-6-acid) (ABTS) is converted into its radical cation (ABTS•+) by addition of sodium persulphate. This blue-green radical cation absorbs light at 734 nm. ABTS•+ is reactive towards most antioxidants. Descriptive statistics, ANOVA, ANCOVA and regression tests and correlation were used to analyze the data using SPSS software version 16., Results: The age of the participants ranged from 21 to 52 years. The mean age of the participants was 30.58 year (±6.97yr). Of all the participants, 28% (n= 53) had no depression symptoms (depression score between 0 and 9), 65.1% (n=123) were categorized as having mild depression (depression score between 10 and 18) and 6.9% (n=13) were categorized as having moderate depression (depression score between 19 and 29). The participants' BMI ranged from 15.9 to 34.3; the mean BMI of the participants was 24.82 kg/m(2) (+ 3.81 kg/m(2)). The mean of the serum TAC level was 2.51 (± 0.56) mg/dl, and the mean serum MDA level was 3.67(± 1.08) μmol/l. There was a significant difference in the mean TAC concentration between the non-depressed group and the group with mild depression (p=0.029)., Conclusion: Depression was associated with reduced mean TAC concentration and an increase in MDA level. There was a linear relationship between the depression score and shift work experience among the rotational shift workers, which showed a high level of stress and depression among the shift-workers.

Inappropriate school bags put students at risk of musculoskeletal problems and early fatigue. Heavy bags can change the body posture and the musculoskeletal system must react appropriately in order to compensate for this stress. It is recommended that the weight of a school bag must not be more than 10% of the student's body weight and the weight must be placed on both shoulders. The present study aimed to identify the risk factors associated with musculoskeletal disorders by comparing the prevalence of musculoskeletal pains among the students. The present descriptive, cross-sectional study was conducted in different educational districts of Shiraz. The study samples were selected using cluster sampling method. In this study, 800 students marked their painful areas on body maps and the SPSS statistical software (v. 11.5) was used to analyze the data. The results showed that among the students who used backpacks, 48.9% carried the weight on both shoulders, 40.4% carried the weight on their right shoulders, and 10.6% used their left shoulders. Besides, 68.02% of the students carrying handbags often used their right shoulders, while 31.98% used their left shoulders. The study results showed that similar to other countries, Iranian students also mostly made use of backpacks. Moreover, the musculoskeletal pains were most prevalent in the shoulders, which is in line with many other studies conducted on the issue.

Background: According to the literature, a large number of people working in industries and service providing personnel, such as firefighters, physicians, and nurses are shift workers. The spread of shift working in industrial societies and the incidence of the problems resulting from shift working have caused the researchers to conduct studies on this issue. The present study also aimed to investigate melatonin and cortisol circadian rhythms in the security guards of Shiraz University of Medical Sciences, Shiraz, Iran., Methods: The present study was conducted on 20 security guards of Shiraz University of Medical Sciences. In order to collect the study data, blood samples were taken from the study subjects in different times of the day (1, 4, 7, 10, 13, 16, 19, and 22) and cortisol and melatonin levels were determined using the radioimmunoassay and enzyme immunoassay techniques, respectively., Results: The results showed that as the intensity of light increased at night, the plasma cortisol level increased, as well. Besides, no statistically significant difference was found between the plasma cortisol levels in natural light and 4500-lux light. On the other hand, a significant difference was observed between the plasma cortisol levels in natural light and 9000-lux light as well as 4500- and 9000-lux lights. The study findings also showed that as the intensity of light increased at night, the plasma melatonin level decreased. In addition, a statistically significant difference was found between the plasma melatonin levels in natural light and 4500-lux light. Nevertheless, no significant difference was observed between the plasma melatonin levels in the natural light and 9000-lux light as well as 4500- and 9000-lux lights., Conclusions: The present study aimed to investigate the subsequences of shift working in the security guards of Shiraz University of Medical Sciences and showed that occupational exposure to bright light could affect some biological markers, such as melatonin and cortisol secretion.